JP1989-039542 A — Hisashi Tokumaru, Masakuni Tai
| 16 ELEMENTS / 13 GROUPS |
| DESIGN 82-195mm |
| F/2.88 DESIGN |
| FRONT FOCUS |
| ALL-SPHERICAL |
CONSTRAINED_RECONSTRUCTION: front focus by patent Group I / production first lens group. The modeled first vertex is fixed and D7 increases by 9.3584-9.3592 mm at 1.8 m; Groups II-IV and the rear image spacing otherwise retain their infinity-focus geometry. MFD is referenced to the modeled image plane.
| Element | Type | Glass |
|---|---|---|
| L1 | Positive Meniscus | S-FSL5 (OHARA catalog equivalent; patent 487701; production supplier unspecified) |
| L2 | Positive Meniscus | S-FSL5 (OHARA catalog equivalent; patent 487701; production supplier unspecified) |
| L3 | Negative Meniscus | 740317 class (vendor unresolved) |
| L4 | Positive Meniscus | 603607 class (vendor unresolved) |
| L5 | Biconcave Negative | 603607 class (vendor unresolved) |
| L6 | Biconcave Negative | 603607 class (vendor unresolved) |
| L7 | Positive Meniscus | FF8 (HOYA catalog equivalent; patent 750251; production supplier unspecified) |
| L8 | Biconcave Negative | 694532 class (vendor unresolved) |
| L9 | Biconvex Positive | 773496 class (vendor unresolved) |
| L10 | Biconvex Positive | S-FSL5 (OHARA catalog equivalent; patent 487701; production supplier unspecified) |
| L11 | Plano-Concave Negative | 740317 class (vendor unresolved) |
| L12 | Biconvex Positive | Unmatched (493836 Minolta AD/ED fluorophosphate; no compatible public coefficient row) |
| L13 | Biconcave Negative | 755275 class (vendor unresolved) |
| L14 | Positive Meniscus | 717295 class (vendor unresolved) |
| L15 | Negative Meniscus | 834372 class (vendor unresolved) |
| L16 | Biconvex Positive | 689311 class (vendor unresolved) |